There will be a change in the Earth's local sub-surface thermal structure before and/or after an earthquake. In this work we have introduced a new parameter (I) which relates integral effect of temperature variation and seismic activity. This parameter in its various forms integrates the temperature variations during one year before and after earthquake. Some recent earthquakes are chosen throughout Iran on Alps-Himalayas fault zone with magnitudes 4.5 and more. Subsurface temperatures up to one meter depth measured in nearby weather stations are used as there is no deeper data available. We found the new defined parameter (I) has a direct relation with earthquakes magnitude (M) and reverse relation with distance (d) between earthquake focus and station in which temperature is measured. Suitable formulas for these relations are suggested regarding the magnitude ranges and time period with respect to the earthquake time. There may be a way to use this new parameter as a quake precursor.